US5481540A - FDDI bridge frame learning and filtering apparatus and method - Google Patents
FDDI bridge frame learning and filtering apparatus and method Download PDFInfo
- Publication number
- US5481540A US5481540A US08/336,887 US33688794A US5481540A US 5481540 A US5481540 A US 5481540A US 33688794 A US33688794 A US 33688794A US 5481540 A US5481540 A US 5481540A
- Authority
- US
- United States
- Prior art keywords
- network
- stations
- messages
- cam
- stored
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L45/00—Routing or path finding of packets in data switching networks
- H04L45/74—Address processing for routing
- H04L45/745—Address table lookup; Address filtering
- H04L45/7453—Address table lookup; Address filtering using hashing
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/46—Interconnection of networks
- H04L12/4604—LAN interconnection over a backbone network, e.g. Internet, Frame Relay
- H04L12/462—LAN interconnection over a bridge based backbone
- H04L12/4625—Single bridge functionality, e.g. connection of two networks over a single bridge
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/42—Loop networks
- H04L12/427—Loop networks with decentralised control
- H04L12/433—Loop networks with decentralised control with asynchronous transmission, e.g. token ring, register insertion
Definitions
- This invention relates generally to fiber distributed data interface (FDDI) bridges, and, in particular, to frame learning and filtering in a transparent bridge that works with FDDI frame transmit/receive apparatus to decide whether or not to receive a frame, and thereafter to further process the frame so as to, for example, transmit on an interconnected network.
- FDDI fiber distributed data interface
- frames or messages transmitted on a transmission medium interconnecting a plurality of transmitter/receiver stations include source address (SA) and destination address (DA) information as well as data. Also connected to the medium are bridges to destinations outside of the first network, for example stations on an interconnected second network.
- SA source address
- DA destination address
- a message When a message is received at a first port in a bridge, it is filtered to decide whether that frame should be forwarded to another port in the bridge for transmission onto the second network. How quickly such a decision can be made largely determines the performance of the bridge. Filtering in a transparent bridge generally involves two different activities. First, a data base of the addresses of the active stations on the local network must be established and maintained. This is done by "learning", i.e., collecting the source addresses of all frames traveling on the network in the data base. Second, for every frame arriving at the bridge, the data base is searched to determine whether the destination address of the arrival frame matches any entries in the data base. If a match exists, it is concluded that the frame is destined for a station on the local network where the port is connected.
- the frame needs no further processing in the bridge.
- the destination is assumed to be a station on a different network, in which case the frame may be further processed and founded to a second port in the bridge for transmission onto the second network.
- a port usually receives all frames, regardless of their destination address and passes them into a buffer memory, while a processor examines every frame in the buffer memory and uses the source and destination address information to determine if the frame is to be output, and to build up and update the SA data base.
- information transmission speeds on the network are relatively slow, (e.g., below 10 Mbs and less than 20 Kf/s) the filtering process just described can adequately be implemented in software.
- speeds of 100 Mbs and a maximum frame rate of greater than 500 K f/s may occur, this approach is not acceptable.
- a bridge connected to an FDDI network preprocesses messages using a hardware based arrangement in which the SA data base is maintained in a content addressable memory (CAM).
- a finite state machine working with the other elements of the FDDI bridge acts as an intelligent controller to select which messages are to be passed to the buffer memory for further processing and ultimate transmission to a station on a remote network. Messages are only passed to the buffer memory if the DA is different from the SA's stored in the CAM, indicating that the message is to be forwarded through the bridge to the second network.
- Circuitry is advantageously provided not only to "teach” the CAM about SA's on the network, but also to monitor information relating to the the last activity in a station associated with a particular SA, so that "stale" SA's can be purged from the CAM.
- the present invention includes a hardware based preprocessor and operates in real time, only a fraction of messages destined for stations remote from the local network are presented to the buffer memory for processing, preventing memory overflow and processor overload. Indeed, it has been found that an order of magnitude improvement in processing efficiency can be obtained, as compared to traditional software learning/filtering apparatus and methods.
- FIG. 1 is a block diagram of an example of a prior art bridge interconnecting first and second local area networks
- FIG. 2 is an overall block diagram illustrating a FDDI bridge which incorporates a filtering and learning arrangement in accordance with the present invention
- FIG. 3 is a more detailed circuit diagram of the bridge 220 in FIG. 2;
- FIG. 4 is a logic flow diagram for finite state machine 313 of FIG. 3.
- FIG. 1 there is shown an overall block diagram illustrating a bridge arrangement of a type used generally in the prior an with respect to local area networks such as Ethernet.
- a communication network supporting packet communications at speeds of about 10 Mbs consists of a series of stations 100 interconnected by a communications medium 101. Also connected to medium 101 at connection point 102 is a bridge designated generally as 120. Other bridges and stations connected to medium 101 each have an assigned destination address (DA) and source address (SA).
- DA destination address
- SA source address
- Messages received in bridge 120 via port 104 are input to a network interface controller 105, which passes data in each received packet, as well as the associated SA and DA, to a buffer memory 107.
- the DA is passed to a processor (CPU) 109 via pathway 108.
- a lookup operation can then be performed in the filtering data base maintained in RAM 111, to match the DA with SA's stored therein. If a match is detected, the message in buffer 107 is discarded, as the message is intended for a station 100 on medium 101.
- the message is further processed, if necessary, and then passed to medium 116 via a second network interface controller 113 and port 114.
- medium 116 is received in bridge 120 via port 114 and network interface controller 113, and are processed in a manner identical to that described above.
- the bridge is bidirectional in its operation.
- bridge 220 includes a filter 235 which in turn comprises a hardware finite state machine 233 interconnected with a content addressable memory (CAM) 234.
- Filter 235 acts as a preprocessor with respect to messages received in bridge 220 from the incoming leg 201 of a transmission medium port circuit 204.
- the transmission medium may be an optical fiber supporting FDDI communication protocol, which interconnects a first network of stations 200. More specifically, before a message is applied to buffer memory 207 for processing, the DA and SA information in the message is passed to filter 235 via link 240.
- the DA is checked with the data base in CAM 234 to determine whether the message should be further processed or dropped.
- This database includes the SA's of stations on the first network, which is dynamically updated as discussed more fully below. If the message is not destined for a station 200, it is entered in buffer memory 207 via path 206, where further processing may (if necessary) be effected under the control of CPU 209 via control signals received on path 208. This is done so that the message can be passed to a second network of stations 230 interconnected by transmission medium 215, 216, which likewise supports the FDDI protocol.
- CPU 209 provides additional control signals to filter 235 via link 232, while control signals in the reverse direction are carried on link 231.
- the functions provided by CPU 209 are largely "administrative".
- Examples of the functions performed are (a) control of the "aging process” by which SA's for inactive stations are periodically removed from the CAM; and (b) compilation of statistics related to the stations 200, 230 on the network (e.g., which stations are active, volume of activity, etc.).
- a second filter 225 comprising finite state machine 223 and CAM 224 may be provided.
- Filter 225 preprocesses messages received from the incoming leg 216 of the second transmission medium via port 214 via network interface controller 213, and applies only those messages destined for stations 200 on the first network interconnected by transmission medium 201, 202 to buffer memory 207 for additional processing.
- bridge 220 is thus arranged symmetrically for processing of bidirectional traffic.
- FIG. 3 is a more, detailed circuit diagram illustrating the arrangement of filter circuits 235 (and 225) of FIG. 2 and its relationship with other portions of bridge 220.
- the apparatus of FIG. 3 includes an FDDI chip set 300 which performs the functions of port circuit 204 and network interface controller 205 of FIG. 2. More specifically, port 303 includes a receiver 304 which provides the connection between the incoming leg 301 of the transmission medium and the bridge, and transmitter 305, which provides the connection between the bridge and outgoing leg 302. Port 303 performs certain FDDI physical layer functions on the data received from and applied to the transmission medium, as is well known. These functions include optical/electrical conversion, for example.
- Network interface controller 309 receives its input from receiver 304 via link 307, and provides outgoing information to transmitter 305 via link 306.
- Several commercially available integrated circuits, such as models 7984, 7985, and 79C81-83 supplied by AMD may provide the functionality of FDDI chip set 300.
- Finite state machine 313, which may be implemented with programmable logic sequencers, such as model 22V10 available from AMD, is arranged to constantly monitor the status of network interface controller 309, via inputs on lines 312, 330 and 361 and to step through a sequence of logical states, illustrated in FIG. 4, when each message is received in the bridge.
- finite state machine 313 When a start of frame delimiter is detected in an incoming frame by network interface controller 309, finite state machine 313 receives an SOF input on line 312 and starts the filtering process by a transition from its idle state 401 to state 402 in which it signals FIFO (first in, first out) register 314 on line 342 to begin reading the destination address (DA) of the message.
- FIFO first in, first out
- CAM content addressable memory
- finite state machine 313 receives the results of a comparison performed by CAM 350 between the data existing in the CAM, representing the SA's of stations connected to the transmission medium from which the message was received, and the DA just written into the comparand register. If the outcome of the comparison is negative, (i.e. there is no match), CAM 350 (in state 414) signals FSM 313 via a "match status" signal on line 360, and FSM 313 in turn signals network interface controller 309 via a "forward" signal on line 311, to copy the incoming frame into buffer memory 207 for further processing. Eventually, this message will be applied to the second network to which the bridge is connected. On the other hand, if there is a match, FSM 313 continues directly to state 405 without copying the message. Thus, the message is intended for and will be made available only to other stations on the first network.
- state 405 a data collection procedure is followed in FSM 313 with respect to the SA contained in the message, wherein the current portion of the SA is captured and written into FIFO 314.
- state 406 the previously stored SA is written to the comparand register of CAM 350, while the present portion is again read.
- a comparison between the SA contained in the comparand register and the stored data in the CAM occurs in state 407, indicating whether the SA already exists in the CAM, or if it should be added into the CAM.
- FSM 313 is signaled by a "match" signal on line 360, and proceeds to state 409, where it reads the internal address of the CAM at which a matched value exists, and latches (stores) the address in latch 322 via an output on line 320. If the SA does not match any stored SA, FSM 313 proceeds to state 408, where it reads out on line 340, the first available location in CAM 350 where the SA can be stored. This internal address is latched (stored) in both latches 318 and 322. The react/write operations in latches 318 and 322 are controlled by outputs from finite state machine 313 on lines 341 and 342, respectively.
- FSM 313 stays at state 408 or 409 until network interface controller 309 signals FSM 313 on line 361 that an ending delimiter (EOF) has been detected in the message. At this point, FSM 313 transitions to state 410 or 411. If a new SA is to be stored in CAM 350, when state 410 is reached, a read command is applied to latch 318 on line 341, so that latch 318 outputs the latched internal address on line 319. Concurrently, control command is issued by FSM 313 to CAM 350 on line 372, to move the SA from the comparand register of the CAM into the CAM array at the address supplied by latch 318.
- EDF ending delimiter
- finite state machine 313 proceeds to state 411, in which the internal address stored in latch 322 is used to update a table maintained in SRAM 324, so that the activity in each station on the network can be monitored.
- SRAM 324 is advantageously arranged to be dual ported, and arranged so that it contains the same number of entries as CAM 350, and so that every address recorded in CAM 350 has a corresponding entry in SRAM 324, at the same location.
- the bridge of FIG. 3 is arranged so that whenever a SA is encountered, the entry in SRAM 324 associated with that SA is cleared (reset to zero), using the first SRAM port, indicating that the SA is current.
- CPU 209 periodically increments all entries in SRAM 324, using the second SRAM port and data/address line 345. As a result, the value of an entry is directly related to the time since the SA was last encountered.
- CPU 209 based on the age of each SA, also controls removal of aged SA's in CAM 350 and the corresponding aging information in SRAM 324. This is done by first periodically reading and comparing stored values in SRAM 324 to a threshold, using the read/write control line 344 to apply stored data on line 345 to CPU 209. When an aged SA is encountered, the internal address is passed to CPU 209 via line 345. The stale SA may then be removed when a remove command is issued to CAM 350 by CPU 209.
- CPU 209 does not participate directly in the filtering process--it simply assists in keeping track of "aging" SA's.
- the bridge arrangement of the present invention can operate much more efficiently than other apparatus presently available.
- finite state machine 313 is arranged to return to idle state 401 after the aging information in SRAM 324 has been updated in state 411. Not shown in FIG. 4 is the fact that the process followed in finite state machine 313 may be prematurely terminated at any time, if an anomalous condition is determined to exist.
- FSM returns directly to idle state 401 from whatever state it is presently in. For example: if the bridge encounters a frame with a format different from the expected format or not supported by the bridge, it will return to state 401. Also, FSM 313 is arranged to return directly to state 402 if, at any time, an SOF signal is detected on line 312. This is done because it is common to encounter packet remnants on the transmission medium. If an SOF signal does occur before the entire process of FIG. 4 is completed, then the packet just processed was in fact a remnant, so that the next packet should then be timely processed.
- Network interface controller 309 is arranged to provide a FRMSTRIPPED signal to FSM 313 via line 330.
- this signal indicates, for example, that the packet originated from the bridge of FIG. 3 itself, rather than from an external station, and therefore the FSM 313 suspends its operation on the current message, and discards the frame without "learning" its SA.
- CAM 350 may be implemented using content addressable memory model 99C10 available from AMD. This circuit is organized internally as a 256 ⁇ 48 bit device, with a 16 bit external I/O bus. A data write moves data from I/O bus 317 into the Comparand Register; a 48 bit write is achieved through three consecutive 16 bit writes. A comparison of the data in the comparand register and in the CAM array occurs automatically after a data write is completed, and an active match status signal on line 360 occurs if there is a match. After a comparison operation, the status will also indicate at which location a match occurred, or if no match occurred, which location is available for storage of new data. Other operations are performed in the CAM through combination of signals applied to bus 317 and line 321.
- a "move" command applied on bus 317 is used to move the 48 bit data from the comparand register to the CAM array where the data is stored.
- An "empty” command on line 321 is used to empty a location in the CAM array, the address of which is provided on bus 317.
- FIG. 3 shows outputs from CAM 350 on lines 320 and 340 for the purpose of supplying internal addresses to latches 318 and 322, if the CAM is implemented using the above identified device from AMD, then this information is available instead on bus 317.
- CPU 209 to CAM 350 Access of CPU 209 to CAM 350 is arbitrated through finite state machine 313; access is granted only when finite state machine 313 is in a standby state. This is accomplished under the control of CPU 209, which extends a CAM SELECT signal to FSM 313 on line 370 when access is desired. If permission is granted, a signal is returned to CPU 209 on line 371. Under these conditions, CPU 209 then enables a local buffer 346 to read and write data from bus 317 at appropriate intervals, so that information may be timely presented at the data input to CAM 350. Buffer 346 also obtains an input from FSM 313 on line 318, indicating that CAM 350 is enabled to be accessed by CPU 209.
- FSM 313 preprocesses messages to determine which ones need to be applied to buffer memory 207, while others are blocked. This frees up CPU 209, and enables the bridge to operate at the high speeds required in FDDI apparatus.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Small-Scale Networks (AREA)
Abstract
Description
Claims (25)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/336,887 US5481540A (en) | 1990-08-24 | 1994-11-10 | FDDI bridge frame learning and filtering apparatus and method |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US57273890A | 1990-08-24 | 1990-08-24 | |
US08/336,887 US5481540A (en) | 1990-08-24 | 1994-11-10 | FDDI bridge frame learning and filtering apparatus and method |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US57273890A Continuation | 1990-08-24 | 1990-08-24 |
Publications (1)
Publication Number | Publication Date |
---|---|
US5481540A true US5481540A (en) | 1996-01-02 |
Family
ID=24289145
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US08/336,887 Expired - Lifetime US5481540A (en) | 1990-08-24 | 1994-11-10 | FDDI bridge frame learning and filtering apparatus and method |
Country Status (1)
Country | Link |
---|---|
US (1) | US5481540A (en) |
Cited By (80)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1997006615A1 (en) * | 1995-08-08 | 1997-02-20 | Broadband Technologies, Inc. | Flag field-based routing mechanism for fiber optic telecommunication system employing sts-based transmission format containing asynchronous transfer mode cells |
US5608726A (en) * | 1995-04-25 | 1997-03-04 | Cabletron Systems, Inc. | Network bridge with multicast forwarding table |
US5680552A (en) * | 1994-09-20 | 1997-10-21 | Lucent Technologies Inc. | Gateway system for interconnecting different data communication networks |
US5684954A (en) * | 1993-03-20 | 1997-11-04 | International Business Machine Corp. | Method and apparatus for providing connection identifier by concatenating CAM's addresses at which containing matched protocol information extracted from multiple protocol header |
US5724507A (en) * | 1994-03-02 | 1998-03-03 | Iwatsuki; Kazuko | Lan adapter for changing control signal to a value indicating silence when the control signal is changed into a value indicating occurrence of transfer request |
US5748633A (en) * | 1995-07-12 | 1998-05-05 | 3Com Corporation | Method and apparatus for the concurrent reception and transmission of packets in a communications internetworking device |
WO1999000950A1 (en) * | 1997-06-30 | 1999-01-07 | Sun Microsystems, Inc. | Trunking support in a high performance network device |
WO1999014904A1 (en) * | 1997-09-17 | 1999-03-25 | Sony Electronics Inc. | Address look-up mechanism in a multi-port bridge for a local area network |
US5920566A (en) * | 1997-06-30 | 1999-07-06 | Sun Microsystems, Inc. | Routing in a multi-layer distributed network element |
US5938736A (en) * | 1997-06-30 | 1999-08-17 | Sun Microsystems, Inc. | Search engine architecture for a high performance multi-layer switch element |
US5940597A (en) * | 1995-01-11 | 1999-08-17 | Sony Corporation | Method and apparatus for periodically updating entries in a content addressable memory |
US6012099A (en) * | 1995-01-11 | 2000-01-04 | Sony Corporation | Method and integrated circuit for high-bandwidth network server interfacing to a local area network |
US6014380A (en) * | 1997-06-30 | 2000-01-11 | Sun Microsystems, Inc. | Mechanism for packet field replacement in a multi-layer distributed network element |
US6018526A (en) * | 1997-02-20 | 2000-01-25 | Macronix America, Inc. | Bridge device with self learning between network media and integrated circuit and method based on the same |
US6041058A (en) * | 1997-09-11 | 2000-03-21 | 3Com Corporation | Hardware filtering method and apparatus |
US6044418A (en) * | 1997-06-30 | 2000-03-28 | Sun Microsystems, Inc. | Method and apparatus for dynamically resizing queues utilizing programmable partition pointers |
US6044087A (en) * | 1997-06-30 | 2000-03-28 | Sun Microsystems, Inc. | Interface for a highly integrated ethernet network element |
US6049528A (en) * | 1997-06-30 | 2000-04-11 | Sun Microsystems, Inc. | Trunking ethernet-compatible networks |
US6052738A (en) * | 1997-06-30 | 2000-04-18 | Sun Microsystems, Inc. | Method and apparatus in a packet routing switch for controlling access at different data rates to a shared memory |
US6081512A (en) * | 1997-06-30 | 2000-06-27 | Sun Microsystems, Inc. | Spanning tree support in a high performance network device |
US6081522A (en) * | 1997-06-30 | 2000-06-27 | Sun Microsystems, Inc. | System and method for a multi-layer network element |
US6088356A (en) * | 1997-06-30 | 2000-07-11 | Sun Microsystems, Inc. | System and method for a multi-layer network element |
WO2000042754A1 (en) * | 1999-01-15 | 2000-07-20 | Nokia Networks Oy | Packet concatenation method and apparatus |
US6094435A (en) * | 1997-06-30 | 2000-07-25 | Sun Microsystems, Inc. | System and method for a quality of service in a multi-layer network element |
US6119196A (en) * | 1997-06-30 | 2000-09-12 | Sun Microsystems, Inc. | System having multiple arbitrating levels for arbitrating access to a shared memory by network ports operating at different data rates |
US6122706A (en) * | 1993-12-22 | 2000-09-19 | Cypress Semiconductor Corporation | Dual-port content addressable memory |
US6128666A (en) * | 1997-06-30 | 2000-10-03 | Sun Microsystems, Inc. | Distributed VLAN mechanism for packet field replacement in a multi-layered switched network element using a control field/signal for indicating modification of a packet with a database search engine |
US6157951A (en) * | 1997-09-17 | 2000-12-05 | Sony Corporation | Dual priority chains for data-communication ports in a multi-port bridge for a local area network |
US6233243B1 (en) | 1997-11-24 | 2001-05-15 | Ascend Communications, Inc. | Method and apparatus for performing cut-through virtual circuit merging |
US6246680B1 (en) | 1997-06-30 | 2001-06-12 | Sun Microsystems, Inc. | Highly integrated multi-layer switch element architecture |
US6256313B1 (en) | 1995-01-11 | 2001-07-03 | Sony Corporation | Triplet architecture in a multi-port bridge for a local area network |
US6301256B1 (en) | 1997-09-17 | 2001-10-09 | Sony Corporation | Selection technique for preventing a source port from becoming a destination port in a multi-port bridge for a local area network |
US6363067B1 (en) | 1997-09-17 | 2002-03-26 | Sony Corporation | Staged partitioned communication bus for a multi-port bridge for a local area network |
US6370142B1 (en) | 1995-07-12 | 2002-04-09 | Nortel Networks Limited | Method and apparatus for performing per-port IP multicast pruning |
US6400715B1 (en) * | 1996-09-18 | 2002-06-04 | Texas Instruments Incorporated | Network address matching circuit and method |
US6442168B1 (en) | 1997-09-17 | 2002-08-27 | Sony Corporation | High speed bus structure in a multi-port bridge for a local area network |
US6446173B1 (en) | 1997-09-17 | 2002-09-03 | Sony Corporation | Memory controller in a multi-port bridge for a local area network |
US6526474B1 (en) | 1999-10-25 | 2003-02-25 | Cisco Technology, Inc. | Content addressable memory (CAM) with accesses to multiple CAM arrays used to generate result for various matching sizes |
US6560610B1 (en) | 1999-08-10 | 2003-05-06 | Washington University | Data structure using a tree bitmap and method for rapid classification of data in a database |
US20030088698A1 (en) * | 2001-11-06 | 2003-05-08 | Inderpreet Singh | VPN failure recovery |
US6606681B1 (en) | 2001-02-23 | 2003-08-12 | Cisco Systems, Inc. | Optimized content addressable memory (CAM) |
US6617879B1 (en) | 1997-09-17 | 2003-09-09 | Sony Corporation | Transparently partitioned communication bus for multi-port bridge for a local area network |
US6658002B1 (en) | 1998-06-30 | 2003-12-02 | Cisco Technology, Inc. | Logical operation unit for packet processing |
US20030231631A1 (en) * | 2002-05-31 | 2003-12-18 | Pullela Venkateshwar Rao | Method and apparatus for processing packets based on information extracted from the packets and context indications such as but not limited to input interface characteristics |
US20040030802A1 (en) * | 2002-08-10 | 2004-02-12 | Eatherton William N. | Performing lookup operations using associative memories optionally including selectively determining which associative memory blocks to use in identifying a result and possibly propagating error indications |
US20040030803A1 (en) * | 2002-08-10 | 2004-02-12 | Eatherton William N. | Performing lookup operations using associative memories optionally including modifying a search key in generating a lookup word and possibly forcing a no-hit indication in response to matching a particular entry |
US6715029B1 (en) | 2002-01-07 | 2004-03-30 | Cisco Technology, Inc. | Method and apparatus for possibly decreasing the number of associative memory entries by supplementing an associative memory result with discriminator bits from an original set of information |
US6717946B1 (en) | 2002-10-31 | 2004-04-06 | Cisco Technology Inc. | Methods and apparatus for mapping ranges of values into unique values of particular use for range matching operations using an associative memory |
US6725326B1 (en) | 2000-08-15 | 2004-04-20 | Cisco Technology, Inc. | Techniques for efficient memory management for longest prefix match problems |
US6738384B1 (en) | 1997-09-17 | 2004-05-18 | Sony Corporation | Technique for optimizing cut-through for broadcast and multi-cast packets in a multi-port bridge for a local area network |
US6775737B1 (en) | 2001-10-09 | 2004-08-10 | Cisco Technology, Inc. | Method and apparatus for allocating and using range identifiers as input values to content-addressable memories |
US20040170172A1 (en) * | 2002-08-10 | 2004-09-02 | Cisco Technology, Inc., A California Corporation | Associative memory entries with force no-hit and priority indications of particular use in implementing policy maps in communication devices |
US20040172346A1 (en) * | 2002-08-10 | 2004-09-02 | Cisco Technology, Inc., A California Corporation | Generating accounting data based on access control list entries |
US20040170171A1 (en) * | 2002-08-10 | 2004-09-02 | Cisco Technology, Inc., A California Corporation | Generating and merging lookup results to apply multiple features |
US20050021752A1 (en) * | 2002-08-10 | 2005-01-27 | Cisco Technology, Inc., A California Corporation | Reverse path forwarding protection of packets using automated population of access control lists based on a forwarding information base |
US6850530B1 (en) * | 2000-02-04 | 2005-02-01 | Cisco Technology, Inc. | Methods and apparatus for providing and obtaining resource usage information |
US6862281B1 (en) | 2001-05-10 | 2005-03-01 | Cisco Technology, Inc. | L4 lookup implementation using efficient CAM organization |
US6871262B1 (en) | 2002-02-14 | 2005-03-22 | Cisco Technology, Inc. | Method and apparatus for matching a string with multiple lookups using a single associative memory |
US20050195949A1 (en) * | 2004-02-26 | 2005-09-08 | Frattura David E. | Status transmission system and method |
US20050195756A1 (en) * | 2004-02-26 | 2005-09-08 | Frattura David E. | Status announcement system and method |
US6961808B1 (en) | 2002-01-08 | 2005-11-01 | Cisco Technology, Inc. | Method and apparatus for implementing and using multiple virtual portions of physical associative memories |
US6970971B1 (en) * | 2002-01-08 | 2005-11-29 | Cisco Technology, Inc. | Method and apparatus for mapping prefixes and values of a hierarchical space to other representations |
US20060036730A1 (en) * | 2004-08-06 | 2006-02-16 | Richard Graham | System and method for address block enhanced dynamic network policy management |
US20060037075A1 (en) * | 2004-03-10 | 2006-02-16 | Frattura David E | Dynamic network detection system and method |
US7002965B1 (en) | 2001-05-21 | 2006-02-21 | Cisco Technology, Inc. | Method and apparatus for using ternary and binary content-addressable memory stages to classify packets |
US7024515B1 (en) | 2002-11-15 | 2006-04-04 | Cisco Technology, Inc. | Methods and apparatus for performing continue actions using an associative memory which might be particularly useful for implementing access control list and quality of service features |
US7028136B1 (en) | 2002-08-10 | 2006-04-11 | Cisco Technology, Inc. | Managing idle time and performing lookup operations to adapt to refresh requirements or operational rates of the particular associative memory or other devices used to implement the system |
US20060106977A1 (en) * | 2002-08-10 | 2006-05-18 | Cisco Technology, Inc. A California Corporation | Performing lookup operations on associative memory entries |
US7065083B1 (en) | 2001-10-04 | 2006-06-20 | Cisco Technology, Inc. | Method and apparatus for dynamically generating lookup words for content-addressable memories |
US20060277187A1 (en) * | 2002-03-01 | 2006-12-07 | Roese John J | Location based data |
US20070078974A1 (en) * | 2005-06-28 | 2007-04-05 | Krishnan Venkatraman G | Time synchronized wireless method and operations |
US7260673B1 (en) | 2001-07-20 | 2007-08-21 | Cisco Technology, Inc. | Method and apparatus for verifying the integrity of a content-addressable memory result |
US7299317B1 (en) | 2002-06-08 | 2007-11-20 | Cisco Technology, Inc. | Assigning prefixes to associative memory classes based on a value of a last bit of each prefix and their use including but not limited to locating a prefix and for maintaining a Patricia tree data structure |
US7313666B1 (en) | 2002-08-10 | 2007-12-25 | Cisco Technology, Inc. | Methods and apparatus for longest common prefix based caching |
US7313667B1 (en) | 2002-08-05 | 2007-12-25 | Cisco Technology, Inc. | Methods and apparatus for mapping fields of entries into new values and combining these mapped values into mapped entries for use in lookup operations such as for packet processing |
US7496035B1 (en) | 2003-01-31 | 2009-02-24 | Cisco Technology, Inc. | Methods and apparatus for defining flow types and instances thereof such as for identifying packets corresponding to instances of the flow types |
US7558775B1 (en) | 2002-06-08 | 2009-07-07 | Cisco Technology, Inc. | Methods and apparatus for maintaining sets of ranges typically using an associative memory and for using these ranges to identify a matching range based on a query point or query range and to maintain sorted elements for use such as in providing priority queue operations |
US7611292B2 (en) | 2004-11-08 | 2009-11-03 | Enterasys Networks, Inc. | Optical interface identification system |
US20100238927A1 (en) * | 2001-10-19 | 2010-09-23 | Brocade Communications Systems, Inc. | Method and system for intelligently forwarding multicast packets |
US8612648B1 (en) * | 2010-07-19 | 2013-12-17 | Xilinx, Inc. | Method and apparatus for implementing quality of service in a data bus interface |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4597078A (en) * | 1983-10-19 | 1986-06-24 | Digital Equipment Corporation | Bridge circuit for interconnecting networks |
US4627052A (en) * | 1984-03-19 | 1986-12-02 | International Computers Limited | Interconnection of communications networks |
US4707827A (en) * | 1986-03-21 | 1987-11-17 | Zenith Electronics Corporation | Bridging techniques for local area networks |
US4860284A (en) * | 1988-04-20 | 1989-08-22 | American Telephone And Telegraph Company, At&T Bell Laboratories | Method and apparatus for identifying location of a lost token signal in a data communication network |
US4914653A (en) * | 1986-12-22 | 1990-04-03 | American Telephone And Telegraph Company | Inter-processor communication protocol |
US4922503A (en) * | 1988-10-28 | 1990-05-01 | Infotron Systems Corporation | Local area network bridge |
US4942571A (en) * | 1987-09-08 | 1990-07-17 | Bergmann Kabelwerke Ag | On-board network for motor vehicles |
US5046065A (en) * | 1988-08-30 | 1991-09-03 | U.S. Philips Corporation | Communication system, a station to be used in such a system, and a gate connecting element to be used in such a system, as well as a device comprising such a gate connecting element |
US5058109A (en) * | 1989-06-28 | 1991-10-15 | Digital Equipment Corporation | Exclusionary network adapter apparatus and related method |
US5136580A (en) * | 1990-05-16 | 1992-08-04 | Microcom Systems, Inc. | Apparatus and method for learning and filtering destination and source addresses in a local area network system |
US5151897A (en) * | 1990-03-20 | 1992-09-29 | Fujitsu Limited | Inter-LAN connection apparatus and inter-LAN connection method |
-
1994
- 1994-11-10 US US08/336,887 patent/US5481540A/en not_active Expired - Lifetime
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4597078A (en) * | 1983-10-19 | 1986-06-24 | Digital Equipment Corporation | Bridge circuit for interconnecting networks |
US4627052A (en) * | 1984-03-19 | 1986-12-02 | International Computers Limited | Interconnection of communications networks |
US4707827A (en) * | 1986-03-21 | 1987-11-17 | Zenith Electronics Corporation | Bridging techniques for local area networks |
US4914653A (en) * | 1986-12-22 | 1990-04-03 | American Telephone And Telegraph Company | Inter-processor communication protocol |
US4942571A (en) * | 1987-09-08 | 1990-07-17 | Bergmann Kabelwerke Ag | On-board network for motor vehicles |
US4860284A (en) * | 1988-04-20 | 1989-08-22 | American Telephone And Telegraph Company, At&T Bell Laboratories | Method and apparatus for identifying location of a lost token signal in a data communication network |
US5046065A (en) * | 1988-08-30 | 1991-09-03 | U.S. Philips Corporation | Communication system, a station to be used in such a system, and a gate connecting element to be used in such a system, as well as a device comprising such a gate connecting element |
US4922503A (en) * | 1988-10-28 | 1990-05-01 | Infotron Systems Corporation | Local area network bridge |
US5058109A (en) * | 1989-06-28 | 1991-10-15 | Digital Equipment Corporation | Exclusionary network adapter apparatus and related method |
US5151897A (en) * | 1990-03-20 | 1992-09-29 | Fujitsu Limited | Inter-LAN connection apparatus and inter-LAN connection method |
US5136580A (en) * | 1990-05-16 | 1992-08-04 | Microcom Systems, Inc. | Apparatus and method for learning and filtering destination and source addresses in a local area network system |
Cited By (117)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5684954A (en) * | 1993-03-20 | 1997-11-04 | International Business Machine Corp. | Method and apparatus for providing connection identifier by concatenating CAM's addresses at which containing matched protocol information extracted from multiple protocol header |
US6122706A (en) * | 1993-12-22 | 2000-09-19 | Cypress Semiconductor Corporation | Dual-port content addressable memory |
US5724507A (en) * | 1994-03-02 | 1998-03-03 | Iwatsuki; Kazuko | Lan adapter for changing control signal to a value indicating silence when the control signal is changed into a value indicating occurrence of transfer request |
US6304916B1 (en) | 1994-03-02 | 2001-10-16 | Hitachi, Ltd. | Lan connection apparatus and method thereof |
US5953508A (en) * | 1994-03-02 | 1999-09-14 | Hitachi, Ltd. | LAN adaptor system for judging a port type from among a plurality of port types in accordance with a content of a control signal |
US5680552A (en) * | 1994-09-20 | 1997-10-21 | Lucent Technologies Inc. | Gateway system for interconnecting different data communication networks |
US5940597A (en) * | 1995-01-11 | 1999-08-17 | Sony Corporation | Method and apparatus for periodically updating entries in a content addressable memory |
US6256313B1 (en) | 1995-01-11 | 2001-07-03 | Sony Corporation | Triplet architecture in a multi-port bridge for a local area network |
US6122667A (en) * | 1995-01-11 | 2000-09-19 | Sony Corporation | Method and integrated circuit for high-bandwidth network server interfacing to a local area network using CSMA/CD |
US6012099A (en) * | 1995-01-11 | 2000-01-04 | Sony Corporation | Method and integrated circuit for high-bandwidth network server interfacing to a local area network |
US6539022B1 (en) | 1995-04-25 | 2003-03-25 | Enterasys Networks, Inc. | Network device with multicast forwarding data |
US5608726A (en) * | 1995-04-25 | 1997-03-04 | Cabletron Systems, Inc. | Network bridge with multicast forwarding table |
US5898686A (en) * | 1995-04-25 | 1999-04-27 | Cabletron Systems, Inc. | Network bridge with multicast forwarding table |
US5748633A (en) * | 1995-07-12 | 1998-05-05 | 3Com Corporation | Method and apparatus for the concurrent reception and transmission of packets in a communications internetworking device |
US6370142B1 (en) | 1995-07-12 | 2002-04-09 | Nortel Networks Limited | Method and apparatus for performing per-port IP multicast pruning |
WO1997006615A1 (en) * | 1995-08-08 | 1997-02-20 | Broadband Technologies, Inc. | Flag field-based routing mechanism for fiber optic telecommunication system employing sts-based transmission format containing asynchronous transfer mode cells |
US5619498A (en) * | 1995-08-08 | 1997-04-08 | Broadband Technologies, Inc. | Flag field-based routing mechanism for fiber optic telecommunication system employing STS-based transmission format containing asynchronous transfer mode cells |
US6400715B1 (en) * | 1996-09-18 | 2002-06-04 | Texas Instruments Incorporated | Network address matching circuit and method |
US6018526A (en) * | 1997-02-20 | 2000-01-25 | Macronix America, Inc. | Bridge device with self learning between network media and integrated circuit and method based on the same |
US6061362A (en) * | 1997-06-30 | 2000-05-09 | Sun Microsystems, Inc. | Interface for a highly integrated ethernet network element |
US6094435A (en) * | 1997-06-30 | 2000-07-25 | Sun Microsystems, Inc. | System and method for a quality of service in a multi-layer network element |
US6049528A (en) * | 1997-06-30 | 2000-04-11 | Sun Microsystems, Inc. | Trunking ethernet-compatible networks |
US6052738A (en) * | 1997-06-30 | 2000-04-18 | Sun Microsystems, Inc. | Method and apparatus in a packet routing switch for controlling access at different data rates to a shared memory |
US5938736A (en) * | 1997-06-30 | 1999-08-17 | Sun Microsystems, Inc. | Search engine architecture for a high performance multi-layer switch element |
US6081512A (en) * | 1997-06-30 | 2000-06-27 | Sun Microsystems, Inc. | Spanning tree support in a high performance network device |
US6081522A (en) * | 1997-06-30 | 2000-06-27 | Sun Microsystems, Inc. | System and method for a multi-layer network element |
US6088356A (en) * | 1997-06-30 | 2000-07-11 | Sun Microsystems, Inc. | System and method for a multi-layer network element |
WO1999000950A1 (en) * | 1997-06-30 | 1999-01-07 | Sun Microsystems, Inc. | Trunking support in a high performance network device |
US6044087A (en) * | 1997-06-30 | 2000-03-28 | Sun Microsystems, Inc. | Interface for a highly integrated ethernet network element |
US6119196A (en) * | 1997-06-30 | 2000-09-12 | Sun Microsystems, Inc. | System having multiple arbitrating levels for arbitrating access to a shared memory by network ports operating at different data rates |
US6044418A (en) * | 1997-06-30 | 2000-03-28 | Sun Microsystems, Inc. | Method and apparatus for dynamically resizing queues utilizing programmable partition pointers |
US5920566A (en) * | 1997-06-30 | 1999-07-06 | Sun Microsystems, Inc. | Routing in a multi-layer distributed network element |
US6128666A (en) * | 1997-06-30 | 2000-10-03 | Sun Microsystems, Inc. | Distributed VLAN mechanism for packet field replacement in a multi-layered switched network element using a control field/signal for indicating modification of a packet with a database search engine |
US6016310A (en) * | 1997-06-30 | 2000-01-18 | Sun Microsystems, Inc. | Trunking support in a high performance network device |
US6014380A (en) * | 1997-06-30 | 2000-01-11 | Sun Microsystems, Inc. | Mechanism for packet field replacement in a multi-layer distributed network element |
US6246680B1 (en) | 1997-06-30 | 2001-06-12 | Sun Microsystems, Inc. | Highly integrated multi-layer switch element architecture |
US6041058A (en) * | 1997-09-11 | 2000-03-21 | 3Com Corporation | Hardware filtering method and apparatus |
US6744728B1 (en) | 1997-09-17 | 2004-06-01 | Sony Corporation & Sony Electronics, Inc. | Data pipeline timing optimization technique in a multi-port bridge for a local area network |
US6617879B1 (en) | 1997-09-17 | 2003-09-09 | Sony Corporation | Transparently partitioned communication bus for multi-port bridge for a local area network |
US6308218B1 (en) | 1997-09-17 | 2001-10-23 | Sony Corporation | Address look-up mechanism in a multi-port bridge for a local area network |
US6363067B1 (en) | 1997-09-17 | 2002-03-26 | Sony Corporation | Staged partitioned communication bus for a multi-port bridge for a local area network |
US6738384B1 (en) | 1997-09-17 | 2004-05-18 | Sony Corporation | Technique for optimizing cut-through for broadcast and multi-cast packets in a multi-port bridge for a local area network |
US6157951A (en) * | 1997-09-17 | 2000-12-05 | Sony Corporation | Dual priority chains for data-communication ports in a multi-port bridge for a local area network |
US6442168B1 (en) | 1997-09-17 | 2002-08-27 | Sony Corporation | High speed bus structure in a multi-port bridge for a local area network |
US6446173B1 (en) | 1997-09-17 | 2002-09-03 | Sony Corporation | Memory controller in a multi-port bridge for a local area network |
WO1999014904A1 (en) * | 1997-09-17 | 1999-03-25 | Sony Electronics Inc. | Address look-up mechanism in a multi-port bridge for a local area network |
US6751225B1 (en) | 1997-09-17 | 2004-06-15 | Sony Corporation | Port within a multi-port bridge including a buffer for storing routing information for data packets received in the port |
US6816490B1 (en) | 1997-09-17 | 2004-11-09 | Sony Corporation | Statistical learning technique in a multi-port bridge for a local area network |
US6301256B1 (en) | 1997-09-17 | 2001-10-09 | Sony Corporation | Selection technique for preventing a source port from becoming a destination port in a multi-port bridge for a local area network |
US6233243B1 (en) | 1997-11-24 | 2001-05-15 | Ascend Communications, Inc. | Method and apparatus for performing cut-through virtual circuit merging |
US6658002B1 (en) | 1998-06-30 | 2003-12-02 | Cisco Technology, Inc. | Logical operation unit for packet processing |
WO2000042754A1 (en) * | 1999-01-15 | 2000-07-20 | Nokia Networks Oy | Packet concatenation method and apparatus |
US6560610B1 (en) | 1999-08-10 | 2003-05-06 | Washington University | Data structure using a tree bitmap and method for rapid classification of data in a database |
US6526474B1 (en) | 1999-10-25 | 2003-02-25 | Cisco Technology, Inc. | Content addressable memory (CAM) with accesses to multiple CAM arrays used to generate result for various matching sizes |
US6850530B1 (en) * | 2000-02-04 | 2005-02-01 | Cisco Technology, Inc. | Methods and apparatus for providing and obtaining resource usage information |
US6725326B1 (en) | 2000-08-15 | 2004-04-20 | Cisco Technology, Inc. | Techniques for efficient memory management for longest prefix match problems |
US6606681B1 (en) | 2001-02-23 | 2003-08-12 | Cisco Systems, Inc. | Optimized content addressable memory (CAM) |
US6862281B1 (en) | 2001-05-10 | 2005-03-01 | Cisco Technology, Inc. | L4 lookup implementation using efficient CAM organization |
US20060104286A1 (en) * | 2001-05-21 | 2006-05-18 | Cisco Technology, Inc., A California Corporation | Using ternary and binary content addressable memory stages to classify information such as packets |
US7002965B1 (en) | 2001-05-21 | 2006-02-21 | Cisco Technology, Inc. | Method and apparatus for using ternary and binary content-addressable memory stages to classify packets |
US7602787B2 (en) | 2001-05-21 | 2009-10-13 | Cisco Technology, Inc. | Using ternary and binary content addressable memory stages to classify information such as packets |
US7260673B1 (en) | 2001-07-20 | 2007-08-21 | Cisco Technology, Inc. | Method and apparatus for verifying the integrity of a content-addressable memory result |
US7065083B1 (en) | 2001-10-04 | 2006-06-20 | Cisco Technology, Inc. | Method and apparatus for dynamically generating lookup words for content-addressable memories |
US6775737B1 (en) | 2001-10-09 | 2004-08-10 | Cisco Technology, Inc. | Method and apparatus for allocating and using range identifiers as input values to content-addressable memories |
US8443103B2 (en) | 2001-10-19 | 2013-05-14 | Foundry Networks, Llc | Method and system for intelligently forwarding multicast packets |
US9112715B2 (en) | 2001-10-19 | 2015-08-18 | Foundry Networks, Llc | Method and system for intelligently forwarding multicast packets |
US20110064078A1 (en) * | 2001-10-19 | 2011-03-17 | Brocade Communications Systems, Inc. | Method and system for intelligently forwarding multicast packets |
US7877508B1 (en) | 2001-10-19 | 2011-01-25 | Foundry Networks, Llc | Method and system for intelligently forwarding multicast packets |
US20100238927A1 (en) * | 2001-10-19 | 2010-09-23 | Brocade Communications Systems, Inc. | Method and system for intelligently forwarding multicast packets |
US7647422B2 (en) | 2001-11-06 | 2010-01-12 | Enterasys Networks, Inc. | VPN failure recovery |
US20030088698A1 (en) * | 2001-11-06 | 2003-05-08 | Inderpreet Singh | VPN failure recovery |
US6715029B1 (en) | 2002-01-07 | 2004-03-30 | Cisco Technology, Inc. | Method and apparatus for possibly decreasing the number of associative memory entries by supplementing an associative memory result with discriminator bits from an original set of information |
US6961808B1 (en) | 2002-01-08 | 2005-11-01 | Cisco Technology, Inc. | Method and apparatus for implementing and using multiple virtual portions of physical associative memories |
US6970971B1 (en) * | 2002-01-08 | 2005-11-29 | Cisco Technology, Inc. | Method and apparatus for mapping prefixes and values of a hierarchical space to other representations |
US6871262B1 (en) | 2002-02-14 | 2005-03-22 | Cisco Technology, Inc. | Method and apparatus for matching a string with multiple lookups using a single associative memory |
US7739402B2 (en) | 2002-03-01 | 2010-06-15 | Enterasys Networks, Inc. | Locating devices in a data network |
US7706369B2 (en) | 2002-03-01 | 2010-04-27 | Enterasys Networks, Inc. | Location discovery in a data network |
US20060277187A1 (en) * | 2002-03-01 | 2006-12-07 | Roese John J | Location based data |
US8972589B2 (en) | 2002-03-01 | 2015-03-03 | Enterasys Networks, Inc. | Location-based access control in a data network |
US7606938B2 (en) | 2002-03-01 | 2009-10-20 | Enterasys Networks, Inc. | Verified device locations in a data network |
US20030231631A1 (en) * | 2002-05-31 | 2003-12-18 | Pullela Venkateshwar Rao | Method and apparatus for processing packets based on information extracted from the packets and context indications such as but not limited to input interface characteristics |
US7336660B2 (en) | 2002-05-31 | 2008-02-26 | Cisco Technology, Inc. | Method and apparatus for processing packets based on information extracted from the packets and context indications such as but not limited to input interface characteristics |
US7558775B1 (en) | 2002-06-08 | 2009-07-07 | Cisco Technology, Inc. | Methods and apparatus for maintaining sets of ranges typically using an associative memory and for using these ranges to identify a matching range based on a query point or query range and to maintain sorted elements for use such as in providing priority queue operations |
US7299317B1 (en) | 2002-06-08 | 2007-11-20 | Cisco Technology, Inc. | Assigning prefixes to associative memory classes based on a value of a last bit of each prefix and their use including but not limited to locating a prefix and for maintaining a Patricia tree data structure |
US7313667B1 (en) | 2002-08-05 | 2007-12-25 | Cisco Technology, Inc. | Methods and apparatus for mapping fields of entries into new values and combining these mapped values into mapped entries for use in lookup operations such as for packet processing |
US7350020B2 (en) | 2002-08-10 | 2008-03-25 | Cisco Technology, Inc. | Generating and merging lookup results to apply multiple features |
US20050021752A1 (en) * | 2002-08-10 | 2005-01-27 | Cisco Technology, Inc., A California Corporation | Reverse path forwarding protection of packets using automated population of access control lists based on a forwarding information base |
US7177978B2 (en) | 2002-08-10 | 2007-02-13 | Cisco Technology, Inc. | Generating and merging lookup results to apply multiple features |
US20040030802A1 (en) * | 2002-08-10 | 2004-02-12 | Eatherton William N. | Performing lookup operations using associative memories optionally including selectively determining which associative memory blocks to use in identifying a result and possibly propagating error indications |
US7237059B2 (en) | 2002-08-10 | 2007-06-26 | Cisco Technology, Inc | Performing lookup operations on associative memory entries |
US7103708B2 (en) | 2002-08-10 | 2006-09-05 | Cisco Technology, Inc. | Performing lookup operations using associative memories optionally including modifying a search key in generating a lookup word and possibly forcing a no-hit indication in response to matching a particular entry |
US7082492B2 (en) | 2002-08-10 | 2006-07-25 | Cisco Technology, Inc. | Associative memory entries with force no-hit and priority indications of particular use in implementing policy maps in communication devices |
US7313666B1 (en) | 2002-08-10 | 2007-12-25 | Cisco Technology, Inc. | Methods and apparatus for longest common prefix based caching |
US7065609B2 (en) | 2002-08-10 | 2006-06-20 | Cisco Technology, Inc. | Performing lookup operations using associative memories optionally including selectively determining which associative memory blocks to use in identifying a result and possibly propagating error indications |
US20060106977A1 (en) * | 2002-08-10 | 2006-05-18 | Cisco Technology, Inc. A California Corporation | Performing lookup operations on associative memory entries |
US7028136B1 (en) | 2002-08-10 | 2006-04-11 | Cisco Technology, Inc. | Managing idle time and performing lookup operations to adapt to refresh requirements or operational rates of the particular associative memory or other devices used to implement the system |
US7349382B2 (en) | 2002-08-10 | 2008-03-25 | Cisco Technology, Inc. | Reverse path forwarding protection of packets using automated population of access control lists based on a forwarding information base |
US7441074B1 (en) | 2002-08-10 | 2008-10-21 | Cisco Technology, Inc. | Methods and apparatus for distributing entries among lookup units and selectively enabling less than all of the lookup units when performing a lookup operation |
US20040030803A1 (en) * | 2002-08-10 | 2004-02-12 | Eatherton William N. | Performing lookup operations using associative memories optionally including modifying a search key in generating a lookup word and possibly forcing a no-hit indication in response to matching a particular entry |
US20040170172A1 (en) * | 2002-08-10 | 2004-09-02 | Cisco Technology, Inc., A California Corporation | Associative memory entries with force no-hit and priority indications of particular use in implementing policy maps in communication devices |
US20040172346A1 (en) * | 2002-08-10 | 2004-09-02 | Cisco Technology, Inc., A California Corporation | Generating accounting data based on access control list entries |
US20040170171A1 (en) * | 2002-08-10 | 2004-09-02 | Cisco Technology, Inc., A California Corporation | Generating and merging lookup results to apply multiple features |
US20070002862A1 (en) * | 2002-08-10 | 2007-01-04 | Cisco Technology, Inc., A California Corporation | Generating and merging lookup results to apply multiple features |
US7689485B2 (en) | 2002-08-10 | 2010-03-30 | Cisco Technology, Inc. | Generating accounting data based on access control list entries |
US6717946B1 (en) | 2002-10-31 | 2004-04-06 | Cisco Technology Inc. | Methods and apparatus for mapping ranges of values into unique values of particular use for range matching operations using an associative memory |
US7024515B1 (en) | 2002-11-15 | 2006-04-04 | Cisco Technology, Inc. | Methods and apparatus for performing continue actions using an associative memory which might be particularly useful for implementing access control list and quality of service features |
US7496035B1 (en) | 2003-01-31 | 2009-02-24 | Cisco Technology, Inc. | Methods and apparatus for defining flow types and instances thereof such as for identifying packets corresponding to instances of the flow types |
US20050195949A1 (en) * | 2004-02-26 | 2005-09-08 | Frattura David E. | Status transmission system and method |
US7580403B2 (en) | 2004-02-26 | 2009-08-25 | Enterasys Networks, Inc. | Status transmission system and method |
US20050195756A1 (en) * | 2004-02-26 | 2005-09-08 | Frattura David E. | Status announcement system and method |
US20060037075A1 (en) * | 2004-03-10 | 2006-02-16 | Frattura David E | Dynamic network detection system and method |
US20060036730A1 (en) * | 2004-08-06 | 2006-02-16 | Richard Graham | System and method for address block enhanced dynamic network policy management |
US7945945B2 (en) | 2004-08-06 | 2011-05-17 | Enterasys Networks, Inc. | System and method for address block enhanced dynamic network policy management |
US7611292B2 (en) | 2004-11-08 | 2009-11-03 | Enterasys Networks, Inc. | Optical interface identification system |
US8086232B2 (en) | 2005-06-28 | 2011-12-27 | Enterasys Networks, Inc. | Time synchronized wireless method and operations |
US20070078974A1 (en) * | 2005-06-28 | 2007-04-05 | Krishnan Venkatraman G | Time synchronized wireless method and operations |
US8612648B1 (en) * | 2010-07-19 | 2013-12-17 | Xilinx, Inc. | Method and apparatus for implementing quality of service in a data bus interface |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5481540A (en) | FDDI bridge frame learning and filtering apparatus and method | |
US5027350A (en) | Method and apparatus for providing a local area network bridge | |
US6292483B1 (en) | Apparatus and method for generating an index key for a network switch routing table using a programmable hash function | |
US6128666A (en) | Distributed VLAN mechanism for packet field replacement in a multi-layered switched network element using a control field/signal for indicating modification of a packet with a database search engine | |
JP2837828B2 (en) | Method and apparatus for changing operation mode of local area network switch | |
US5838915A (en) | System for buffering data in the network having a linked list for each of said plurality of queues | |
US5691984A (en) | Compact, adaptable brouting switch | |
US6762995B1 (en) | Network switch including hysteresis in signalling fullness of transmit queues | |
JP4663828B2 (en) | Bridge device having self-learning function between network media and integrated circuit and method based thereon | |
US5638515A (en) | Method for stripping dataframes from the communicating medium in an FDDI communications network | |
EP0409539B1 (en) | Frame routing method for communication networks | |
US7688825B2 (en) | Filtering frames at an input port of a switch | |
EP0954139A1 (en) | Methods of altering dynamic decision trees | |
JPH10178442A (en) | Network repeater | |
JP2001223749A (en) | Packet classification engine | |
CN113490084B (en) | FC-AE exchanger ultra-bandwidth transmission method supporting priority scheduling | |
JPH07183898A (en) | Method for recovering predetermined order for cell style of asymmetric order in atm exchange technology | |
US5862344A (en) | Apparatus and methods for routing data packets through a processing system network | |
EP0954140A1 (en) | Method of managing dynamic decision trees | |
US6438129B1 (en) | Restriction of source address look-ups in network | |
US6529507B1 (en) | Restriction of source address up-dating in network switches | |
JPH05260060A (en) | Communication equipment | |
US6987761B2 (en) | Inbound data stream controller with pre-recognition of frame sequence | |
JP4252379B2 (en) | Variable length frame buffer device | |
JPH0697965A (en) | Relay control system for router |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: AT&T CORP., NEW YORK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:AMERICAN TELELPHONE AND TELEGRAPH COMPANY;REEL/FRAME:007527/0274 Effective date: 19940420 Owner name: AT&T IPM CORP., FLORIDA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:AT&T CORP.;REEL/FRAME:007528/0038 Effective date: 19950523 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
FEPP | Fee payment procedure |
Free format text: PAYER NUMBER DE-ASSIGNED (ORIGINAL EVENT CODE: RMPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 8 |
|
REMI | Maintenance fee reminder mailed | ||
AS | Assignment |
Owner name: AGERE SYSTEMS, INC., PENNSYLVANIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:AT&T CORP.;LUCENT TECHNOLOGIES INC.;REEL/FRAME:015980/0280;SIGNING DATES FROM 19960329 TO 20020531 |
|
FPAY | Fee payment |
Year of fee payment: 12 |